Molding machine

Abstract

A molding machine includes a mold space between two mold carriers. One of the two mold carriers is movable relative to the other by a drive. A separate power unit generates a predetermined closing force between the two mold carriers when the two mold carriers are moved together. The separate power unit comprises, for its actuation, a pressure cushion filled with a composition that is highly viscous by comparison with hydraulic oil.

I claim:  
     
       1. A molding machine, comprising: 
       two mold carriers defining a mold space therebetween, wherein one of said two mold carriers is movable relative to the other of said two mold carriers;  
       a drive for moving said one of said two mold carriers; and  
       a power unit for generating a predetermined closing force between said two mold carriers when said two mold carriers are moved together, wherein the separate power unit comprises a pressure cushion filled with a highly viscous composition that has a viscosity greater than that of hydraulic oil.  
     
     
       2. The molding machine of  claim 1 , wherein said drive comprises an electromechanical drive. 
     
     
       3. The molding machine of  claim 2 , wherein said drive comprises a ball-rolling spindle drive. 
     
     
       4. The molding machine of  claim 2 , wherein said drive comprises a hollow-shafted motor, a spindle and a spindle nut and wherein said hollow-shafted motor is operatively connected for effecting linear movement of said spindle. 
     
     
       5. The molding machine of  claim 1 , further comprising a pressure cylinder, wherein said pressure cylinder and said drive are supported on the same part of said molding machine, and wherein said pressure cushion is disposed in said pressure cylinder. 
     
     
       6. The molding machine of  claim 5 , further comprising an auxiliary piston arranged for generating the pressure of said pressure cushion, wherein a piston surface of said auxiliary piston is smaller than a piston surface of said pressure cylinder. 
     
     
       7. The molding machine of  claim 6 , further comprising an electromechanical linear drive operatively arranged for moving said auxiliary piston. 
     
     
       8. The molding machine of  claim 1 , wherein said highly viscous composition comprises grease. 
     
     
       9. The molding machine of  claim 1 , wherein said molding machine comprises an injection molding machine and said mold carriers comprise mold mounting plates. 
     
     
       10. The molding machine of  claim 9 , wherein said injection molding machine comprises a tiebarless injection molding machine and further comprises a C-shaped shackle and a third plate, wherein said third plate and said other of said two molded carriers are retained at said C-shaped shackle and wherein said drive for said one of said two mold carriers is supported on one of said third plate and said other of said two mold carriers.